Portable flaring apparatus

ABSTRACT

A portable flaring apparatus is disclosed. The flaring apparatus comprises a stack comprising multiple segments of varying diameters, which may be configured to be telescoped for transport. The flaring apparatus further comprises one or more inlets for the intake of gas, an arrester for suppressing flames and detonation within the flaring system, and a plurality of combustion tips for flaring gas. The components of the flaring apparatus may be affixed to a trailer platform for portability.

RELATED APPLICATION DATA

This application is a division of U.S. patent application Ser. No.16/883,329, filed May 26, 2020, which claims the benefit of and priorityunder 35 U.S.C. § 119(e) to U.S. Patent Application No. 62/968,031,filed Jan. 30, 2020, entitled “PORTABLE FLARE TOWER,” which isincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present disclosure is generally directed to devices, systems andmethods for emissions control. In particular, the present disclosureprovides devices, systems and methods for flaring excess natural gasfrom an abandoned oil or gas well.

BACKGROUND OF THE INVENTION

An oil or gas well is plugged and abandoned when it is no longer of use.Several steps must be performed in the abandonment process in order toensure that the abandoned well does not pose a risk to public health orsafety. These steps are generally governed by federal, state, and localregulations, as well as industry standards and practices.

One such step involves burning off excess gas prior to plugging theabandoned well, a process known as “flaring.” Flaring traditionallyinvolves piping gas into an array of combustible flare tips that useelectricity to ignite the gas. The flare tips are disposed within astack, similar to a smoke stack, which directs the emissions and otherbyproducts of the flaring process upward toward the atmosphere. However,several other components are necessary in the flaring apparatus in orderto ensure the safe and proper flow of gas toward the burners as well asthe safe and proper venting of emissions.

It is inefficient for well operators to construct flaring equipment at awell that is to be abandoned. Accordingly, there is a need for aportable flaring apparatus including a portable stack that can betransported to the sites of abandoned wells in order to flare the excessgas. A key challenge in portable flaring apparatuses involves the stack,which must be of a sufficient height for proper venting of emissions.The required size of the tower poses challenges for portability of theapparatus, as large stacks are difficult to transport safely.

Additionally, there is a need to maximize the number of flare tips inorder to flare excess gas as quickly and efficiently as possible. Thenumber of flare tips is limited by the size of the stack, the maximumdensity of the flare tip array that can be achieved withoutinappropriately compromising safety, and the maximum burn and flow rateavailable in the apparatus without inappropriately compromising safety.Accordingly, a need exists for robust flaring apparatuses that cansupport high flaring rates and high gas flows.

SUMMARY OF THE INVENTION

It is an object of the present disclosure to provide a portable flaringapparatus that includes a flare toward that can be transported safelyand efficiently while providing enough protection for high rates offlaring.

It is a further object of the present disclosure to provide a portableflaring apparatus with components that allow for high rates of flaringwithout creating undue health or safety risk.

Aspects of the present disclosure include a portable apparatus that maybe mounted on a trailer platform. The apparatus comprises a flamesuppressor, which may be a detonation flame arrester, of sufficientstrength to allow for the safe flaring of gas at a high rate.

Aspects of the present disclosure include a portable stack. The stackmay comprise multiple segments of varying diameters that can betelescoped in order to reduce the height of the stack during transport.Aspects of the present disclosure further include a portable stackcomprising an interior shaft and an exterior shaft, thereby fortifyingthe strength of the stack.

BRIEF DESCRIPTION OF THE DRAWINGS

The exemplary embodiments of the invention will be described in detail,with reference to the following figures wherein:

FIG. 1 depicts a portable flaring apparatus in accordance with oneembodiment of the present disclosure;

FIG. 2 depicts a stack in accordance with one embodiment of the presentdisclosure;

FIG. 3 depicts a stack in accordance with one embodiment of the presentdisclosure;

FIG. 4 depicts a stack in accordance with one embodiment of the presentdisclosure;

FIG. 4A depicts a stack in accordance with one embodiment of the presentdisclosure;

FIG. 5 depicts a blast arrester for use with one embodiment of thepresent disclosure;

FIG. 6 depicts a combustion tip assembly in accordance with oneembodiment of the present disclosure; and

FIG. 7 depicts a combustion tip in accordance with one embodiment of thepresent disclosure.

DETAILED DESCRIPTION

A portable flaring apparatus is described herein. An exemplaryapplication for the portable flaring apparatus is burn off of naturalgas from oil and gas extraction wells.

An embodiment of the present disclosure will be described in referenceto FIG. 1 .

The apparatus is disposed upon a movable platform 10 such as a trailer.Preferably certain components are securely attached to the platform.

The apparatus comprises one or more inlets 20 (in a preferredembodiment, there are two inlets) connected to a volume pot 30 or othercomponent in which liquid may be separated from natural gas. The volumepot is connected to a meter pipe 40 associated with a meter 50. Themeter pipe is connected to a master control valve 60 which can be usedto shut off the flow of gas. The master control valve is connected to adevice 70 configured to substantially prevent the transmission offlames, such as a flame arrester, detonation arrester, detonation flamearrester, or blast arrester. Such a component is configured to allow theflow of gas but substantially prevent the energy from combustion fromtraveling back through the connecting pipe toward the volume pot. Such adevice may operate, for example, by lowering the temperature of the gasto prevent combustion, venting energy, absorbing energy, or acombination of such operations. The device will be referred to as a“blast arrester.”

The blast arrester is connected to a manifold 80 comprising a pluralityof connections 90 with associated valves 100 and joiners 110, allowingthe connections to be independently opened, closed, and/or detached (ina preferred embodiment, there are five connections). The connections areconnected to a plurality of combustion tips 120 configured to combustnatural gas. In a preferred embodiment, the combustion tips areelectrically ignitable. The combustion tips are disposed within a burnerbox 130.

A stack 140 is disposed surrounding the combustion tips. In a preferredembodiment, the stack is polygonal in shape. In one embodiment, thestack is hexagonal in shape.

The stack may take various forms. In one embodiment, the stack comprisesa plurality of movable telescoping segments 150 of varying sizes suchthat the segments can be nested within each other for transport. In oneembodiment, shown in FIG. 2 , the stack comprises four such segments 150a, 150 b, 150 c, and 150 d, of substantially the same height but varyingwidths. In a separate embodiment, shown in FIG. 3 , the stack comprisestwo such segments 150 e and 150 f, wherein the top segment 150 f islarger in width than the bottom segment 150 e and approximately twicethe height of the bottom segment. In a further embodiment the topsegment 150 f is formed from two subsegments 150 f and 150 f′, which arelarger in width than the bottom segment but substantially equal inheight to the bottom segment, welded together. The segments may takevarious shapes and sizes. The stack may be non-telescoping. The stackmay comprise a single segment. The stack may comprise a single segmentformed of welded subsegments. The stack may comprise one or moresegments formed of welded subsegments.

The stack may comprise a cylindrical interior shaft 160 surrounded by apolygonal exterior shaft 170, such as an octagonal shaft, as shown inFIG. 4 . The polygonal exterior shaft may be comprised of expanded metalgrating 240 as shown in FIG. 4A, and may comprise a plurality oftelescoping or non-telescoping segments.

In a preferred embodiment, a second platform 180 is disposed on themovable platform 10 on which the stack 140 is disposed. In thisembodiment, the top of the burner box 130 is substantially coplanar withthe top surface of the second platform 180. The bottom of the burner boxmay be substantially coplanar with the top surface of the movableplatform 10.

A hydraulic assembly 190 may be disposed on the platform to control thetelescoping stack, i.e. to move the movable segments up and down. In apreferred embodiment the hydraulic assembly comprises a hydraulic pump200, a hydraulic tank 210, and hydraulic controls 220.

A plurality of adjustable air intake mechanisms 230 may be configured onthe exterior of the stack to control the flow of air through the stackto ensure even burning by the combustion tips.

The various connections may be metal pipes or other suitableconnections.

The number of combustion tips may be determined based on the size of atleast the bottom stack segment. It will be understood that a maximumnumber of combustion tips can be determined based on the area inside thestack and the minimum spacing required between combustion tips for safeoperation.

Operation of the portable flaring apparatus will now be described withreference to a preferred embodiment.

The movable platform is transported to a site requiring natural gascombustion, such as an oil well that is to be capped and abandoned. Inthis embodiment, the telescoping stack consists of a first hexagonalsegment and a second hexagonal segment having a diameter larger than thefirst hexagonal segment and a height twice the height of the firsthexagonal segment. The second hexagonal segment is formed of twohexagonal subsegments having the same height as the first hexagonalsegment welded together. In transport mode, the second hexagonal segmentis in a lowered position such that the height of the stack is minimizedto facilitate safe transport. For example, the bottom of the secondsegment may be substantially coplanar with the surface of the secondplatform when in transport mode. At the site, the apparatus is placed injob mode and the hydraulic assembly is used to cause the secondhexagonal segment to move upward until the bottom of the secondhexagonal segment is substantially coplanar with the top of the firsthexagonal segment.

Two inlets of the portable flaring apparatus are secured to the outletsof an external separator. Gas enters the apparatus from an externalseparator through the two inlets. Gas flows into the volume pot, whereany residual liquid present in the gas is condensed and removed. Gasexits the pot and flows through the meter pipe, causing the associatedmeter to display a value associated with at least the gas and/or the gasflow. The gas then flows through the master control valve and throughthe blast arrester toward the manifold. At the manifold, the gas flowsthrough any of the plurality of connections that are attached and haveopen valves. The gas then flows to the combustion tips disposed in aburner box within the stack, which are ignited by electric currents orvoltages in order to burn the gas.

The blast arrester substantially ensures that the combustion occurringin the stack does not cause excessive heat, energy, or heated and/orcombusting gas to flow backwards through the system toward the volumepot, preventing a dangerous condition. The blast arrester must be ofsuitable strength to vent or otherwise absorb the energy from thecombustion without incurring significant damage.

The master control valve is operable to stop the flow of gas from thevolume pot through the blast arrester to the manifold. However, it willbe understood that the master control valve can be installed at variouspoints in the flow, including between the inlet(s) and the volume pot,between the volume pot and the blast arrester, or between the blastarrester and the manifold.

The stack may comprise one or more vents.

An aspect of the present disclosure is that the stack is permanently ina vertical position with respect to the movable platform and/or secondplatform. That is, the stack need not be moved from a horizontal to avertical position for operation.

In one embodiment of the present disclosure, the blast arrester is aGroth Model 7658A unstable detonation flame arrester as shown in FIG. 5. The document titled “Installation, Operation and Maintenance Manualfor Stable Detonation Flame Arrester” for Model 7658A, available athttps://www.grothcorp.com/wp-content/uploads/2019/10/IOM-for-Model-7658AS-Stable-Detonation.pdf,from which FIG. 5 has been reproduced, is incorporated by reference.

In one embodiment of the present disclosure, the combustion tips have a1- to 5-inch nipple and a 3-inch rosebud head, with a 9/64-inch orificeand a ¾-inch pilot assembly. A detailed illustration of the combustiontip assembly shown in FIG. 1 using combustion tips according to thesedimensions is illustrated in FIG. 6 . An example combustion tipaccording to these dimensions is illustrated in FIG. 7 .

The present disclosure includes any one or more of the exampleembodiments as substantially disclosed herein optionally in combinationwith any one or more other aspects/embodiments as substantiallydisclosed herein.

The present disclosure includes one or more means adapted to perform anyone or more of the above example embodiments as substantially disclosedherein.

The phrases “at least one,” “one or more,” “or,” and “and/or” areopen-ended expressions that are both conjunctive and disjunctive inoperation. For example, each of the expressions “at least one of A, Band C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “oneor more of A, B, or C,” “A, B, and/or C,” and “A, B, or C” means Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, or A, B and C together.

The term “a” or “an” entity refers to one or more of that entity. Assuch, the terms “a” (or “an”), “one or more,” and “at least one” can beused interchangeably herein. It is also to be noted that the terms“comprising,” “including,” and “having” can be used interchangeably.

What is claimed is:
 1. An apparatus comprising: at least one inlet; anarrester; a stack; and a plurality of combustion tips disposed withinthe circumference of said stack; wherein said stack comprises: a firstsegment; and a second segment of smaller diameter than said firstsegment; and wherein said second segment is configured to be disposedwithin said first segment in a first configuration of said stack, andsaid second segment is configured to be substantially below said firstsegment in a second configuration of said stack.
 2. The apparatus ofclaim 1, wherein said arrester is a detonation flame arrester.
 3. Theapparatus of claim 1, wherein said first segment and said second segmentare polygonal in shape.
 4. The apparatus of claim 1, wherein said firstsegment and said second segment are substantially circular in shape. 5.The apparatus of claim 1, wherein said second segment is of a firstheight, and said first segment is of a second height approximately twicesaid first height.
 6. The apparatus of claim 5, wherein said firstsegment comprises two subsegments, wherein each subsegment isapproximately of said first height.
 7. The apparatus of claim 1, whereinsaid stack further comprises: a third segment of smaller diameter thansaid second segment, wherein said third segment is configured to bedisposed within said second segment in a third configuration of saidstack, and said third segment is configured to be substantially belowsaid second segment in a fourth configuration of said stack; and afourth segment of smaller diameter than said third segment, wherein saidfourth segment is configured to be disposed within said third segment ina fifth configuration of said stack, and said fourth segment isconfigured to be substantially below said third segment in a sixthconfiguration of said stack.
 8. The apparatus of claim 1, wherein saidfirst segment and said second segment are hexagonal in shape.
 9. Anapparatus comprising: a trailer, said trailer comprising: a platform; atleast one inlet; an arrester; a stack; and a plurality of combustiontips disposed within the circumference of said stack; wherein said stackcomprises: a first segment; and a second segment of smaller diameterthan said first segment; wherein said at least one inlet, said arrester,and said stack are affixed to said platform; and wherein said secondsegment is configured to be disposed within said first segment in afirst configuration of said stack, and said second segment is configuredto be substantially below said first segment in a second configurationof said stack.
 10. The apparatus of claim 9, wherein said second segmentis of a first height, and said first segment is of a second heightapproximately twice said first height.
 11. The apparatus of claim 10,wherein said first segment comprises two subsegments, wherein eachsubsegment is approximately of said first height.
 12. The apparatus ofclaim 9, said stack further comprising: a third segment of smallerdiameter than said second segment, wherein said third segment isconfigured to be disposed within said second segment in a thirdconfiguration of said stack, and said third segment is configured to besubstantially below said second segment in a fourth configuration ofsaid stack; and a fourth segment of smaller diameter than said thirdsegment, wherein said fourth segment is configured to be disposed withinsaid third segment in a fifth configuration of said stack, and saidfourth segment is configured to be substantially below said thirdsegment in a sixth configuration of said stack.